Understanding Window Energy Efficiency

Replacing the windows in your home can
dramatically reduce your monthly heating and
cooling bills. Additionally, replacing
your windows with energy efficient windows can
even help you qualify for a tax credit.
There are several aspects of an energy efficient
window to consider. Terms like U-factor,
Low-E, Energy Star, SHGC and others should all
be properly understood to better evaluate your
window choices. Further, it is also a good
idea to look for energy efficiency
rated labels on your new windows. Common
labels you'll see will refer to the National
Fenestration Rating Council (NFRC) which is a
group that provides accurate information on the
efficiency of the windows. Lastly,
identifying an
ENERGY STAR® logo on your window will
ensure that your windows are energy efficient.

Energy Efficiency Common Terms:

Low-E Coating

This is a coating that prevents the heat from transferring
back through the windows. Low-E stands for 'low emissivity'.
This particular coating is also good for protecting your home's
interiors (furniture, floors, carpet, etc.) from fading from
sunlight.

Argon/Krypton Filled Windows

These are types of gas found between the panes of glass in
your window. Since argon and krypton gas are more dense
than the atmosphere, more energy efficiency is gained by having
the gas between the panes of glass versus just air between the
panes of glass. Argon and krypton gas are colorless,
tasteless and odorless so they are not harmful in the event of a
leak.

R-Value

This refers to resistance to heat flow. If the R value
is higher, there is more resistance to heat flow meaning it is a
stronger insulator.

U-Value

This term is similar to R-Value in that it applies to heat
insulation. U-Value is the inverse of R-Value so with this
term, the lower the U-Value the better the insulation.

Dual Pane Windows

This is a window with two layers of glass typically with a
gas in between. Dual pane windows help prevent heat loss.

Triple Pane Windows

This is a window with three layers of glass typically with a
gas in between each. Triple pane windows help prevent heat
loss and are typically used only in extreme climates.

Window Glazing

This is a glaze applied directly to the glass on your
windows. There are single glazed windows, double glazed
windows, triple glazed windows and tinted windows. These
various reflective coatings are designed to help heating and
cooling performance. Using a glaze combined with a gas
between the panes (like Argon or Krypton) will dramatically
increase the energy efficiency of your windows.

SHGC

This acronym stands for Solar Heat Gain Coefficient and it is
a measurement of how well a window blocks the heat produced from
sunlight. SHGC values are between 0 and 1 which represents
the fraction of the heat from the sun that enters through the
window. The lower the SHGC value, the less heat that is
transmitted from the sun through the window.

Help Finding a Contractor who offers Energy Efficient
Windows

We offer
Free Window Quotes
from top quality contractors who are in your
local area. Our contractors are reliable and have
extensive knowledge about energy efficient replacement windows.
Replacement windows are a great
way to increase the value of your home as well as reduce your
monthly heating and cooling costs. The service we provide to help
you is free with no obligations.